Nail-driving machine



2 Shets-Sheet 2.

r E. MERRITT.

NAIL DRIVING MACHINE.

(No Model.)

No. 278,252. Patented May 22,1883.

UNITED .STATES PATENT OFFICE:

EDVVARI) MERRITT OF BROOKTON, MASSACHUSETTS.

NAIL-DRIVING MACHINE.

SPECIFICATION forming part of Letters Patent No. 278,252, dated May 22, 1888,

Application filed September 8, 1882. (No modclll To all whom it may concern:

Be it known that I, EDWARD MERRITT, a citizen of the United States,residing at Brockton, in the county of Plymouth and State of 5 Massachusetts, have inventedcertain new and useful Improvements in Nail -Drivin9 Machines; .and I do hereby declare that the same are fully described in the following specification and illustrated in theaccompanying drawlngs.

My invention relates to improvements in nail-driving machines; and it has for its objects the provision of means to produce a constant though varying pressure of the work against the throat or the presser-foot of the machine, and to provide means for clinching the nails in work having curved or irregular surfaces.

The invention is carried out as follows, reference being had to the accompanying drawings, where-- Figure 1 is a side elevation, partly in section, of a nailing-machine embodying my invention. Fig. 2 is a front elevation. Fig. 3 is a plan view of the upper end of the horn; and Fig. 4 is a vertical section of the horn, clinching-cup, nail-throat, and a piece of work.

Like letters refer to like partsin all the-tigures.

A represents the fixed head of the machine, provided with the vertically-operated presserloot B and nail-feeding mechanism 0. The swinging head D, in which the awl E and driver F are alternately operated, is pivotally supported bya standard,A, on thefixed head A. In the fixed head A, as shown by dotted lines, Fig. 1, is journaleda rock-shaft, A one arm, A, of which is provided with a i'rictionroller,,which rides in the groove of a cam, A on the main shaft G, and the other arm'of which, being slotted,is connected to the swinging head D by a sliding block on a bolt or stud, a, secured by a thumb-nut in a slot in the face of thegswinging head D, by which means the pointof'connection of said arm and head may be adjustably fixed nearer to or farther from the axial line of the rock-shaft A and the length of the oscillation or extent of the swinging movement of the head D regulated. To the swinging head D is attached a rigid throat, H,which therefore partakes of the movements of the head D.

I represents the horn, which at its upper end is provided with a clinching-cup, J, having a central depending lug, j. The cup J is adapted by the concavity of its upper surface to turn the point. of a nail coming-in contact therewith upward into the material through which it is driven, and by the convexity of the bearing-surface of the cup, in connection with the concave recess tof the horn I, it automatically adjusts itself to uneven, irregular,

in said aperture can occur. The lower end of the born I is pivotally secured to one end of a T- lever, K, and the weight of the horn is overbalanced by a weight, L, adjustably secured to the opposite end of said lever, while the third branch thereof is pivotally secured to a bracket, M, formed on the standard M of the machine, said pivotal attachment being atm, or as nearly on a level with the bottom of the throat H as practicable. In the bracket M, outside of the pivot m, a second lever, N, is pivoted, and its upper end is curved to bear against the face of a cam, N, fixed to the end of the main shaft G, and it has a depression, at, on its face. The lower end of the lever N is provided with a spring, 0, comprising two or more leaves adjustably secured upon each other by the bolts 0 0, passing through slots therein, whereby the outer leaf or leaves may be moved upon the inner from or toward its end, so as to increase ordiminish the stiffness of the spring as a whole, and its lower end being seated in an aperture, k, in the lever K, back of its pivot, the pressure of the spring against the lever may be regulated as to its quantity, while its constancy is maintained by the upper end of the lever N bearing against the face of the cam N during all the operations of the machine, except the feeding of the material, when the upper end of said lever is 02. A bracket, N is formed on the front of the standard M, and slotted to act as a guide for the lever K, and a treadle, Q, and rod R are provided for the purpose of withdrawing the front end of the lever and the horn I, supported thereon, from the throat H, to allow the work to be placed on the born.

This being the construction, the operation is as follows: After the work has been placed on the born I the pressure on the treadle Q, is released and the horn rises by the action of the weight L and spring 0 until the work is pressed against the throat H. If you now startthe machine, the presser-foo't B is forced down by the action of its cam, (not shown in the drawings,) which is on the main shaft Gr, causing the work and born to be forced away from the throat against the action of the weight and spring. The function of said presser-foot B is to press the work and horn away from the throat H to allow the latter and its swinging head D to swing back the distance required for the feed between the nails. The driver F now begins to rise and the swinging head D begins its backward stroke. When the head has reached the extent of its backward stroke the presser-foot rises and allows the work. and the born I to be forced upward against the throat H, and the awl E descends and enters the work. Now the upper end of the lever N enters the depression a on the cam N, thereby wholly releasing the pressure of the spring 0 on the horn, leaving the weight L to press the horn upward to such an extent only as notto interfere with the feeding of the work over the end of the horn by the forward stroke of the swinging head D, with its awl E in the work, which now ensues. When the head D has reached the limit of its forward stroke the increased pressure of the spring 0 on the horn I is now caused by the action of the cam N on the upper end of the lever Nto force and hold the work against the throat H while the awl E is being withdrawn from the work, and the nailenters the perforation made by the awl and is being driven by the driver F. This operation is repeated until the whole of the shoe-sole or work has been nailed, after which the horn I is withdrawn and another shoe or piece of work placed on the horn, ready for nailing.

Having thus fully described my invention, what I claim is' 1. In a nail-driving machine, a counterbalanced suspended horn, in combination .with a rigid throat and vertically-operating presserfoot, substantially as shown and described.

2. A counterbalanced suspended horn, combined with a rigid throat and a vertically-operating presser-foot, and with means, su bstantially as described, for sustaining a constant and varying pressure of the horn against the same, substantially as and for the purpose set forth.

3. A counterbalanced suspended horn, combined with a vertically-operating presser-foot, and a swinging head provided with a rigid throat, substantially as and for the purpose set forth.

4. The combination of a swinging head provided with a rigid throat, a driver and an awl, and a horn having a concave seat, anda clinching-cup having a convexouter bearingsurface, adapted to rest in the concave seat and to automatically adjust itself to the surface of the work, substantially as described.

5. The combination of a horn havingaconcave seat and a clinching-cup having a convex outer bearing-surface adapted to rest in the concave seat, substantially as described.

6. The combination of a horn having a perforated concave seat and a clinching-cup having a convex outer bearing-surface and a central depending lug smaller than the perforations in the seat, substantially as shown and described.

7. The combination of a suspended T-lever, a horn pivoted to one arm thereof, a weight adjustably secured to the opposite arm thereof, and a spring arranged in rear of the point of suspension, and means, substantially as described, for intermittently removing the pressure of said spring, substantially as shown and described.

8. In a nailing-machine, the combination of the rigid throat H, the revolving horn I, ar-' ranged upon the suspended leverK, the adjustable counter-balance L on said lever K, the variable spring 0, and the treadle Q, connect ed to lever K, as and for the purpose set forth.

9. In a nailing-machine, the combination, with the main shaft, of an end cam provided with a recess, a lever sliding thereon and adapted to variably press a horn against a presser-foot or throat, and an intermediate cam adapted, through the medium of a rock-shaft, to oscillate a swinging head provided with said throat, substantially as shown and described.

10. The combination of the end cam, the lever provided with an adjustable spring, and the suspended horn,-substantially as shown and described.

In testimony whereof I have affixed my signature in presence of two witnesses.

EDWARD MERRITT.

Witnesses HENRY OHADBOURN, JAMES W. WATSON. 

